/* ===== CSS Custom Properties (Theming) ===== */
:root {
  --accent: #c62828;
  --accent-light: #ef5350;
  --accent-dark: #8e0000;
  --bg: #fafafa;
  --bg-alt: #f0f0f0;
  --card-bg: #ffffff;
  --text: #1a1a1a;
  --text-muted: #666;
  --nav-bg: #ffffff;
  --nav-text: #333;
  --footer-bg: #1a1a1a;
  --footer-text: #ccc;
  --shadow: 0 2px 12px rgba(0,0,0,0.08);
  --shadow-hover: 0 6px 24px rgba(0,0,0,0.14);
  --border: #e0e0e0;
  --radius: 10px;
  --transition: 0.3s ease;
}

/* ===== Dark Mode ===== */
[data-theme="dark"] {
  --bg: #121212;
  --bg-alt: #1e1e1e;
  --card-bg: #242424;
  --text: #e0e0e0;
  --text-muted: #aaa;
  --nav-bg: #1a1a1a;
  --nav-text: #e0e0e0;
  --footer-bg: #0a0a0a;
  --footer-text: #999;
  --shadow: 0 2px 12px rgba(0,0,0,0.3);
  --shadow-hover: 0 6px 24px rgba(0,0,0,0.45);
  --border: #333;
}

/* ===== Accent Themes ===== */
[data-accent="red"]    { --accent: #c62828; --accent-light: #ef5350; --accent-dark: #8e0000; }
[data-accent="blue"]   { --accent: #1565c0; --accent-light: #42a5f5; --accent-dark: #003c8f; }
[data-accent="teal"]   { --accent: #00796b; --accent-light: #48a999; --accent-dark: #004c40; }
[data-accent="purple"] { --accent: #6a1b9a; --accent-light: #9c4dcc; --accent-dark: #38006b; }
[data-accent="orange"] { --accent: #e65100; --accent-light: #ff833a; --accent-dark: #ac1900; }

/* ===== Base Reset & Typography ===== */
*, *::before, *::after { box-sizing: border-box; }

body, html {
  height: 100%;
  margin: 0;
  line-height: 1.7;
}

body {
  font-family: 'Raleway', 'Segoe UI', sans-serif;
  background: var(--bg);
  color: var(--text);
  transition: background var(--transition), color var(--transition);
}

h1, h2, h3, h4, h5, h6 {
  font-family: 'Raleway', sans-serif;
  color: var(--text);
  font-weight: 700;
}

p { color: var(--text); }

a { color: var(--accent); transition: color var(--transition); }
a:hover { color: var(--accent-light); }

/* ===== Navigation ===== */
.site-nav {
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  z-index: 1000;
  background: var(--nav-bg);
  box-shadow: var(--shadow);
  transition: background var(--transition);
}

.site-nav .nav-inner {
  max-width: 1200px;
  margin: 0 auto;
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 0 24px;
  height: 60px;
}

.site-nav .nav-brand {
  font-size: 1.15rem;
  font-weight: 800;
  color: var(--text);
  text-decoration: none;
  letter-spacing: 1px;
  text-transform: uppercase;
}
.site-nav .nav-brand:hover { color: var(--accent); }

.site-nav .nav-links { display: flex; gap: 4px; align-items: center; }

.site-nav .nav-links a {
  color: var(--nav-text);
  text-decoration: none;
  padding: 8px 16px;
  border-radius: 6px;
  font-size: 0.9rem;
  font-weight: 500;
  transition: background var(--transition), color var(--transition);
}
.site-nav .nav-links a:hover {
  background: var(--accent);
  color: #fff;
}

.site-nav .nav-links i { margin-right: 6px; }

.nav-toggle {
  display: none;
  background: none;
  border: none;
  font-size: 1.4rem;
  color: var(--text);
  cursor: pointer;
  padding: 8px;
}

/* Mobile sidebar */
.mobile-sidebar {
  position: fixed;
  top: 0;
  left: 0;
  width: 260px;
  height: 100%;
  background: var(--card-bg);
  z-index: 2000;
  transform: translateX(-100%);
  transition: transform 0.3s ease;
  box-shadow: 4px 0 20px rgba(0,0,0,0.2);
  padding-top: 20px;
}
.mobile-sidebar.open { transform: translateX(0); }

.mobile-sidebar a {
  display: block;
  padding: 14px 24px;
  color: var(--text);
  text-decoration: none;
  font-weight: 500;
  border-bottom: 1px solid var(--border);
  transition: background var(--transition);
}
.mobile-sidebar a:hover { background: var(--bg-alt); }

.sidebar-overlay {
  position: fixed;
  inset: 0;
  background: rgba(0,0,0,0.4);
  z-index: 1999;
  display: none;
}
.sidebar-overlay.open { display: block; }

@media (max-width: 768px) {
  .site-nav .nav-links { display: none; }
  .nav-toggle { display: block; }
}

/* ===== Hero Header ===== */
.hero {
  position: relative;
  background-position: center;
  background-size: cover;
  min-height: 340px;
  display: flex;
  align-items: flex-end;
  justify-content: center;
  margin-top: 60px;
}

.hero::after {
  content: '';
  position: absolute;
  inset: 0;
  background: linear-gradient(transparent 30%, rgba(0,0,0,0.65));
}

.hero-content {
  position: relative;
  z-index: 1;
  text-align: center;
  padding: 40px 20px;
  color: #fff;
}

.hero-content h1 {
  color: #fff;
  font-size: 2.8rem;
  margin: 0 0 8px;
  text-shadow: 0 2px 8px rgba(0,0,0,0.4);
}

.hero-content p {
  color: rgba(255,255,255,0.9);
  font-size: 1.1rem;
  margin: 0;
}

.hero-btn {
  display: inline-block;
  margin-top: 16px;
  padding: 10px 28px;
  background: rgba(255,255,255,0.2);
  color: #fff;
  text-decoration: none;
  border-radius: 30px;
  backdrop-filter: blur(4px);
  border: 1px solid rgba(255,255,255,0.3);
  font-weight: 600;
  transition: background 0.3s;
}
.hero-btn:hover { background: var(--accent); color: #fff; border-color: var(--accent); }

/* ===== Sections ===== */
.section {
  padding: 60px 24px;
  max-width: 1200px;
  margin: 0 auto;
}

.section-title {
  text-align: center;
  font-size: 2rem;
  margin-bottom: 40px;
  position: relative;
}
.section-title::after {
  content: '';
  display: block;
  width: 60px;
  height: 3px;
  background: var(--accent);
  margin: 12px auto 0;
  border-radius: 2px;
}

/* ===== Team Members ===== */
.team-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
  gap: 24px;
}

.team-card {
  background: var(--card-bg);
  border-radius: var(--radius);
  box-shadow: var(--shadow);
  padding: 28px 20px;
  text-align: center;
  transition: transform var(--transition), box-shadow var(--transition), background var(--transition);
}
.team-card:hover {
  transform: translateY(-4px);
  box-shadow: var(--shadow-hover);
}

.team-card .headshot {
  width: 140px;
  height: 140px;
  border-radius: 50%;
  object-fit: cover;
  margin: 0 auto 16px;
  display: block;
  border: 3px solid var(--accent);
  transition: border-color var(--transition);
}

.team-card h4 {
  margin: 0 0 4px;
  font-size: 1.1rem;
}

.team-card .email {
  color: var(--accent);
  font-size: 0.85rem;
  margin: 0 0 10px;
}

.team-card .bio {
  font-size: 0.88rem;
  color: var(--text-muted);
  line-height: 1.5;
}

/* ===== About / Feature Cards ===== */
.about-section {
  background: var(--bg-alt);
  transition: background var(--transition);
}

.features-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
  gap: 24px;
}

.feature-card {
  background: var(--card-bg);
  border-radius: var(--radius);
  box-shadow: var(--shadow);
  padding: 32px 24px;
  text-align: center;
  border-top: 4px solid var(--accent);
  transition: transform var(--transition), box-shadow var(--transition), background var(--transition);
}
.feature-card:hover {
  transform: translateY(-4px);
  box-shadow: var(--shadow-hover);
}

.feature-card i {
  font-size: 2rem;
  color: var(--accent);
  margin-bottom: 12px;
}

.feature-card p {
  color: var(--text-muted);
  font-size: 0.95rem;
  line-height: 1.6;
}

/* ===== Labs Grid ===== */
.labs-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(320px, 1fr));
  gap: 28px;
}

.lab-card {
  background: var(--card-bg);
  border-radius: var(--radius);
  box-shadow: var(--shadow);
  overflow: hidden;
  transition: transform var(--transition), box-shadow var(--transition), background var(--transition);
}
.lab-card:hover {
  transform: translateY(-4px);
  box-shadow: var(--shadow-hover);
}

.lab-card img {
  width: 100%;
  height: 220px;
  object-fit: cover;
  display: block;
}

.lab-card-body {
  padding: 24px;
}

.lab-card-body h3 {
  margin: 0 0 8px;
  font-size: 1.25rem;
}

.lab-card-body p {
  color: var(--text-muted);
  font-size: 0.92rem;
  margin-bottom: 16px;
}

.btn {
  display: inline-block;
  padding: 10px 24px;
  background: var(--accent);
  color: #fff;
  text-decoration: none;
  border-radius: 6px;
  font-weight: 600;
  font-size: 0.9rem;
  transition: background var(--transition);
  border: none;
  cursor: pointer;
}
.btn:hover { background: var(--accent-dark); color: #fff; }

.btn-outline {
  background: transparent;
  color: var(--accent);
  border: 2px solid var(--accent);
}
.btn-outline:hover { background: var(--accent); color: #fff; }

/* ===== Lab Report Content ===== */
.lab-content {
  max-width: 960px;
  margin: 80px auto 0;
  padding: 40px 24px;
}

.lab-content h1 {
  font-size: 1.8rem;
  border-bottom: 2px solid var(--accent);
  padding-bottom: 8px;
  margin-top: 40px;
}

.lab-content iframe,
.lab-content object {
  border-radius: var(--radius);
  margin: 20px 0;
}

/* ===== Footer ===== */
.site-footer {
  background: var(--footer-bg);
  color: var(--footer-text);
  text-align: center;
  padding: 40px 24px;
  transition: background var(--transition);
}

.site-footer a {
  color: var(--footer-text);
  text-decoration: none;
  transition: color var(--transition);
}
.site-footer a:hover { color: var(--accent-light); }

.footer-nav {
  display: flex;
  justify-content: center;
  gap: 16px;
  flex-wrap: wrap;
  margin-bottom: 16px;
}

.footer-nav .btn {
  background: rgba(255,255,255,0.1);
  color: var(--footer-text);
}
.footer-nav .btn:hover { background: var(--accent); color: #fff; }

.site-footer .credit {
  font-size: 0.8rem;
  margin-top: 16px;
  opacity: 0.6;
}

/* ===== Theme Switcher ===== */
.theme-toggle-btn {
  position: fixed;
  bottom: 24px;
  right: 24px;
  z-index: 3000;
  width: 50px;
  height: 50px;
  border-radius: 50%;
  background: var(--accent);
  color: #fff;
  border: none;
  cursor: pointer;
  font-size: 1.3rem;
  box-shadow: 0 4px 16px rgba(0,0,0,0.25);
  display: flex;
  align-items: center;
  justify-content: center;
  transition: background var(--transition), transform 0.2s;
}
.theme-toggle-btn:hover { transform: scale(1.1); }

.theme-panel {
  position: fixed;
  bottom: 86px;
  right: 24px;
  z-index: 3000;
  background: var(--card-bg);
  border-radius: var(--radius);
  box-shadow: 0 8px 32px rgba(0,0,0,0.2);
  padding: 20px;
  display: none;
  min-width: 200px;
  transition: background var(--transition);
}
.theme-panel.open { display: block; }

.theme-panel h4 {
  margin: 0 0 12px;
  font-size: 0.85rem;
  text-transform: uppercase;
  letter-spacing: 1px;
  color: var(--text-muted);
}

.color-swatches {
  display: flex;
  gap: 10px;
  margin-bottom: 18px;
}

.color-swatch {
  width: 32px;
  height: 32px;
  border-radius: 50%;
  border: 3px solid transparent;
  cursor: pointer;
  transition: transform 0.2s, border-color 0.2s;
}
.color-swatch:hover { transform: scale(1.15); }
.color-swatch.active { border-color: var(--text); transform: scale(1.15); }

.color-swatch[data-color="red"]    { background: #c62828; }
.color-swatch[data-color="blue"]   { background: #1565c0; }
.color-swatch[data-color="teal"]   { background: #00796b; }
.color-swatch[data-color="purple"] { background: #6a1b9a; }
.color-swatch[data-color="orange"] { background: #e65100; }

.dark-toggle {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 10px;
}

.dark-toggle span {
  font-size: 0.9rem;
  color: var(--text);
}

/* Toggle switch */
.switch {
  position: relative;
  width: 46px;
  height: 24px;
}
.switch input { opacity: 0; width: 0; height: 0; }
.slider {
  position: absolute;
  inset: 0;
  background: var(--border);
  border-radius: 24px;
  cursor: pointer;
  transition: background 0.3s;
}
.slider::before {
  content: '';
  position: absolute;
  width: 18px;
  height: 18px;
  left: 3px;
  bottom: 3px;
  background: #fff;
  border-radius: 50%;
  transition: transform 0.3s;
}
.switch input:checked + .slider { background: var(--accent); }
.switch input:checked + .slider::before { transform: translateX(22px); }

/* ===== Intro / Loading Screen ===== */
.intro-screen {
  position: fixed;
  inset: 0;
  z-index: 10000;
  background: var(--bg);
  display: flex;
  align-items: center;
  justify-content: center;
  flex-direction: column;
  overflow: hidden;
  transition: opacity 0.6s ease, visibility 0.6s ease;
}
.intro-screen.done {
  opacity: 0;
  visibility: hidden;
  pointer-events: none;
}

.intro-text {
  font-family: 'Raleway', sans-serif;
  font-size: 1.6rem;
  font-weight: 800;
  color: var(--text);
  letter-spacing: 2px;
  text-transform: uppercase;
  opacity: 0;
  animation: intro-fade-in 0.5s 1.2s ease forwards;
}

@keyframes intro-fade-in {
  to { opacity: 1; }
}

/* Road */
.intro-road {
  position: absolute;
  left: 0;
  right: 0;
  bottom: 42%;
  height: 40px;
  background: #444;
  border-top: 3px solid #666;
  border-bottom: 3px solid #666;
}
[data-theme="dark"] .intro-road {
  background: #555;
  border-color: #777;
}
.intro-road::after {
  content: '';
  position: absolute;
  top: 50%;
  left: 0;
  right: 0;
  height: 3px;
  background: repeating-linear-gradient(90deg, #f5c518 0, #f5c518 30px, transparent 30px, transparent 60px);
  transform: translateY(-50%);
}

/* Car */
.intro-car {
  position: absolute;
  bottom: calc(42% + 40px);
  left: -180px;
  animation: car-drive 3s ease-in-out forwards;
}

@keyframes car-drive {
  0%   { left: -180px; }
  40%  { left: calc(50% - 60px); }
  60%  { left: calc(50% - 60px); }
  100% { left: calc(100% + 200px); }
}

.car-body {
  position: relative;
  width: 120px;
  height: 35px;
  background: var(--accent);
  border-radius: 5px 10px 0 0;
}

.car-cabin {
  position: absolute;
  top: -22px;
  left: 25px;
  width: 60px;
  height: 24px;
  background: var(--accent-dark);
  border-radius: 8px 8px 0 0;
}

.car-cabin::before,
.car-cabin::after {
  content: '';
  position: absolute;
  top: 4px;
  width: 22px;
  height: 14px;
  background: rgba(173, 216, 230, 0.7);
  border-radius: 3px;
}
.car-cabin::before { left: 5px; }
.car-cabin::after { right: 5px; }

.car-base {
  position: relative;
  width: 130px;
  height: 10px;
  background: var(--accent-dark);
  border-radius: 0 0 3px 3px;
  left: -5px;
}

.car-wheel {
  position: absolute;
  bottom: -10px;
  width: 22px;
  height: 22px;
  background: #333;
  border-radius: 50%;
  border: 3px solid #666;
  animation: wheel-spin 0.4s linear infinite;
}
.car-wheel::after {
  content: '';
  position: absolute;
  top: 50%;
  left: 50%;
  width: 8px;
  height: 8px;
  background: #999;
  border-radius: 50%;
  transform: translate(-50%, -50%);
}
.car-wheel-front { right: 8px; }
.car-wheel-back  { left: 8px; }

@keyframes wheel-spin {
  to { transform: rotate(360deg); }
}

/* Exhaust puffs */
.car-exhaust {
  position: absolute;
  left: -8px;
  bottom: 2px;
  width: 12px;
  height: 12px;
  background: rgba(150,150,150,0.5);
  border-radius: 50%;
  animation: puff 0.6s ease-out infinite;
}
.car-exhaust:nth-child(2) { animation-delay: 0.2s; left: -18px; bottom: 6px; }
.car-exhaust:nth-child(3) { animation-delay: 0.4s; left: -28px; bottom: 10px; }

@keyframes puff {
  0%   { opacity: 0.6; transform: scale(0.5); }
  100% { opacity: 0; transform: scale(2) translateX(-10px); }
}

/* ===== Team Card Drive-Up Animation ===== */
.team-card {
  position: relative;
  overflow: visible;
}

.team-card.animate-init {
  opacity: 0;
  transform: translateY(100vh);
}

.team-card.animate-drive {
  animation: card-drive-up 1.4s ease-out forwards;
}

@keyframes card-drive-up {
  0%   { opacity: 1; transform: translateY(100vh); }
  60%  { opacity: 1; transform: translateY(-14px); }
  75%  { opacity: 1; transform: translateY(5px); }
  88%  { opacity: 1; transform: translateY(-2px); }
  100% { opacity: 1; transform: translateY(0); }
}

/* Mini car that carries each team card */
.mini-car-wrap {
  position: absolute;
  bottom: -28px;
  left: 50%;
  transform: translateX(-50%);
  opacity: 0;
  pointer-events: none;
  z-index: -1;
}

.animate-drive .mini-car-wrap {
  animation: mini-car-show 1.4s ease-out forwards;
}

@keyframes mini-car-show {
  0%   { opacity: 1; }
  70%  { opacity: 1; }
  100% { opacity: 0; }
}

.mini-car-body {
  width: 70px;
  height: 18px;
  background: var(--accent);
  border-radius: 4px 8px 2px 2px;
  position: relative;
}

.mini-car-cabin {
  position: absolute;
  top: -13px;
  left: 16px;
  width: 32px;
  height: 14px;
  background: var(--accent-dark);
  border-radius: 5px 5px 0 0;
}

.mini-car-cabin::before {
  content: '';
  position: absolute;
  top: 2px;
  left: 4px;
  right: 4px;
  height: 8px;
  background: rgba(173, 216, 230, 0.6);
  border-radius: 2px;
}

.mini-wheel {
  position: absolute;
  bottom: -7px;
  width: 14px;
  height: 14px;
  background: #333;
  border-radius: 50%;
  border: 2px solid #555;
}

.mini-wheel::after {
  content: '';
  position: absolute;
  top: 50%;
  left: 50%;
  width: 5px;
  height: 5px;
  background: #888;
  border-radius: 50%;
  transform: translate(-50%, -50%);
}

.mini-wheel-back  { left: 5px; }
.mini-wheel-front { right: 5px; }

.animate-drive .mini-wheel {
  animation: wheel-spin 0.3s linear infinite;
}

/* Mini exhaust */
.mini-exhaust {
  position: absolute;
  left: -5px;
  bottom: 0;
  width: 8px;
  height: 8px;
  background: rgba(150,150,150,0.4);
  border-radius: 50%;
  opacity: 0;
}

.animate-drive .mini-exhaust {
  animation: puff 0.5s ease-out infinite;
}
.animate-drive .mini-exhaust:nth-child(2) {
  animation-delay: 0.15s;
  left: -12px;
  bottom: 3px;
}

/* ===== Nav Robot Hover Tooltips ===== */
.nav-links a {
  position: relative;
}

.nav-links a::before {
  content: attr(data-robot);
  position: absolute;
  top: -48px;
  left: 50%;
  transform: translateX(-50%) scale(0);
  font-size: 2rem;
  line-height: 1;
  opacity: 0;
  transition: transform 0.3s cubic-bezier(0.34, 1.56, 0.64, 1), opacity 0.2s ease;
  pointer-events: none;
  filter: drop-shadow(0 2px 4px rgba(0,0,0,0.2));
  z-index: 10;
}

.nav-links a:hover::before {
  transform: translateX(-50%) scale(1);
  opacity: 1;
  animation: robot-bounce 0.6s ease infinite;
}

@keyframes robot-bounce {
  0%, 100% { transform: translateX(-50%) scale(1) translateY(0); }
  50%      { transform: translateX(-50%) scale(1) translateY(-6px); }
}